Research shows that sex-offender recidivism differs for various types of sex offenders. Men convicted of sex offenses against their own children have the lowest rates of recidivism (less than 10 percent). Exhibitionists and voyeurs tend to have the highest recidivism rates, with some studies reporting rates that exceed 40 percent. Rapists apparently reoffend less often than exhibitionists and voyeurs but more often than incest offenders. This is also true for pedophiles who have offended against nonrelatives. The overwhelming evidence from research is that sex offenders respond to deviant sexual cues to a much larger degree than individuals who have never committed sexual offenses. Research indicates that various types of offenders hold attitudes, beliefs, and sexual arousal patterns that tend to fuel their criminal behaviors. Research pertinent to sex-offender treatment shows that sex offenders are a diverse group and require thorough assessments that will permit individualized offender-treatment matching. Facilities are needed for conducting assessments of sexual arousal to identify those offenders who have deviant sexual preferences and who need special treatment that targets this problem.